Many two door vehicles exist in the market place. It is however desirable to allow the occupants of a rear seat in the vehicle ample space to enter and exit to the rear seats. Many examples exist in the prior art of such structures, allowing the ingress/egress of an occupant from the rear seat by tilting the seat back of the front seat thus releasing a moveable track in relation to a fixed track allowing the front seat to slide to a full extent in a forward position thus allowing occupants of the rear seat ample space to exit or enter the rear seat. Some examples exist in the prior art of seat tracks which have double sets of tracks. These tracks include a lower fixed track, fixed to the vehicle frame, a lower moveable track slidable on the fixed track, a upper fixed track fixed to the lower moveable track and a upper moveable track moveable with respect to the upper fixed track. Such an assembly provides for maximum comfort for the ingress/egress of occupants of a rear seat. One of the difficulties however, for an occupant of a front seat is that each time the rear seat passengers exit or enter the vehicle, a pre-adjusted position set by the front seat occupant may be lost.
Thus, a distinct advantage is obtained to the seat occupant when a memory is provided for the front seat occupants. When the front seat occupants therefor pre-adjust their seat to a predetermine position of comfort for each user, it is desirable that this position be remembered by the seat assembly and maintained inspite of the easy entry seat assembly provided.
Examples exit in the prior art of a seat mechanism having memory in conjunction with the easy entry feature. Often it is the case that the memory is established on either the inboard or outboard rails only, wherein the latching of the seat to an adjusted position is provided by one mechanism and the establishment of the memory is provided by a second separate mechanism. The easy entry feature may be provided by a third mechanism. These mechanism are often very complex and involved requiring a considerable number of latching segments. These assembly because of there complexity may prove to be unreliable in the long term.
U.S. Pat. No. 4,101,169 to the Nissan Motor Company describes a seat structure having a memory and providing an easy entry assembly. The memory is provided on the outboard side of the assembly only. A separate latch is provided on the inboard side which is made dependant on the outboard latch. However, once the easy entry position is reached by the seat with the seat back in a pivoted position if the seat is returned to the pre-set adjusted position it will travel beyond that established point with the seat back pivoted. Also it would be advantageous to have the memory located on both the inboard and outboard sides of the seat assembly. It also would be advantageous to provided the memory function, coincidence with the comforts setting of the seat assembly.
U.S. Pat. No. 4,440,442 to General Motors also is an example of a memory in a seat track which is dependant upon the operation of the seat back. No locking of the seat will occur until the seat back is an upright position. Again the mechanisms with the seat track provide for a single mechanism for memory and a separate mechanism for the comfort adjustment. The memory is located on the outboard side only of the track assembly and there is no latching mechanism on the inboard side which raises the question as to reliability of this mechanism. It would be advantageous if the comfort setting and the memory were conveniently provided in a single functioning latch mechanism.
U.S. Pat. No. 3,940,182 to the Nissan Motors Company provides a more complex memory mechanism which is actuated by a rotatable shaft and includes two latches with required plates. The assembly of this latch may be difficult. Again the memory is located on the outboard side only with a latch mechanism located on the outboard side which also cooperatively engages an dependant inboard latch mechanism. Again it would be advantageous to include comfort and memory settings which are defined by one mechanism. Further it would be advantageous to simplify the structure so it is easy to manufacture and assemble.
U.S. Pat. No. 4,648,657 to the Atwood Vacuum Machine Company describes a complicated seat track assembly which includes three outboard levers for comfort adjustment. The levers are dependant upon one another. Again it would be advantages to provide a simpler mechanism which is easier to assemble and manufacture.
U.S. Pat. No. 4,852,846 to General Motors provides a seat assembly which includes fixed notches used in conjunction with a rotating member. Such an assembly would be complex to assemble and have tight tolerances of manufacture. Again the memory is on the outboard side only and the inboard latch mechanism is dependant on the outboard latch mechanism for operation.
U.S. Pat. No. 4,671,571 to General Motors is another example of an assembly where the memory is dependant on the pivoting of the seat back to an upright position. If the seat were moved rearwardly after reaching the most forward easy entry position without the seat back in an upright position, then from the description at column 3, line 54 to 60 the seat will travel beyond its pre-set position. Further, a considerable effort is required to adjust the seat, since the initial frictional engagement of the memory bar and its lugs must be overcome during the comfort adjustment. It would be beneficial if this design were simplified and if the multiple latch mechanisms were integrated into a single functioning memory and comfort adjustment. Simplification may be a great improvement in reliably as well.
U.S. Pat. No. 4,881,774 to Bertrand Faure Automobile describes a memory seat track assembly which has a memory, which allows a user to allow ingress/egress of a passenger from the rear seat and a return of the seat to its pre set position. However, the mechanism used is complicated and requires both a track latch mechanism and a separate memory lock mechanism for operation. It again would be beneficial if the mechanisms were integrated into one positive mechanism which provides both the comfort and memory setting.
Finally U.S. Pat. No. 4,961,559 to Chrysler describes a seat track assembly having a comfort adjustment but no memory. The seat is also not an easy entry seat.
Nowhere within the prior art is there found a track assembly which includes a unitary memory and comfort latch mechanism in a easy entry seat track assembly which provides for latching on both the inboard and outboard rails separately and coincidentally which improves both the safety and reliability of the seat track assembly.
It is therefore a primary object to this invention to simplify the seat track assemblies of the prior art, and provide a safer and more reliable assembly.
It is a further object of the invention to provide a seat track assembly for an easy entry application which is easy to use and which automatically disengages the seat track from the comfort position to allow ingress and egress of a occupant of a rear seat, and provides a memory to re establish the comfort position.
Further and other objects of the invention will become apparent to a man skilled in the art when considering the following summary of the invention and the more detail description of the preferred embodiments illustrated herein.